Longest stretch of readings within a tolerance

A factory sensor logs one temperature reading per second. Quality control wants the longest stretch of consecutive readings that stays within a tolerance band.

Write longest_subarray_within_limit(nums, limit) that returns the length of the longest such stretch.

Input and output:

• nums: a list of 1 to 100,000 integers, each between -2,147,483,648 and 2,147,483,647.
• limit: an integer between 0 and 4,294,967,295.
• Returns an integer.

Rules:

• A stretch is a contiguous, non-empty run of the list.
• A stretch is within the band when every two readings in it differ by at most limit.
• A single reading is always within the band, so the answer is at least 1.